Pebble is one of the pets I still need and currently working on. I parked a toon in Therazane's Throne and it's been more than a week since I last saw this quest. I am only at 2/10 for the pet. This is making me extremely sad (and frustrated). Why can't Blizz make this quest appear more often?

Feel your pain, I had this one in the works for a very long time. I took a break to play other games and was still at 6/10 when I came back, I did finish it about a month ago though was pretty happy about that. I would have to say I maybe got the quest 1 day out of a week. I unfortunately could not check every day, so it's likely I missed a few opportunities. On average I would say I checked 6 days out of 7.

I did the same thing though, I parked an alt there and made it a quick check to see if it was up.

Likewise, it took me quite a while to get him, checking every day and waiting on the quest. Fortunately I was doing it on a mage so 'porting around was easy (remember there's a portal to Therazane's Throne from the Temple of Earth once you've done the chain). It did happen eventually, and he's one of the highest-hp pets once you level him.

It took me several weeks to get him. last 3 quests had over 2 weeks between them.But just keep checking, it only costs like 5-10 minutes to get to SW, take the portal to deepholme, take the portal to therazane and then go back.

Pebble is an amazing battle pet to have! He kicks butt against mechanical pets! Just hang in there and keep checking every day! I remember how long it took me to finally get Pebble! :S And I also only did it once! I was super happy when Blizz announced pets to become account wide! Good luck!